Sensing system and device

ABSTRACT

A novel device and system are provided for the detection of overheated journals and bearings on a moving vehicle. In one embodiment retroreflective material is propelled to the roadway beneath the vehicle, e.g., a train, to form a target. The target is then exclusively detected by an optical scanner located on a rearward portion of the vehicle.

United States Patent 1191 Warren et a1.

11] 3,727,045 51 Apr. 10, 1973 SENSING SYSTEM AND DEVICE [75] Inventors: Joseph M. Warren, White Bear Lake; Richard S. Wilcox, Marine on St. Croix, both of Minn.

[73] Assignee: Minnesota Mining and Manufacturing Company, Saint Paul, Minn.

[22] Filed: Dec. 28, 1970 [21] App1.No.: 101,518

[52] C1. ..246/l69 A, 1 16/1 14.5 [51] 1 Int. Cl. ..B60q 9/00 [58] Field of Search ..340/280, 231;

[56] 1 References Cited 7 UNITED STATESPATENTS 3,062,176 11/1962 Willia.rns....' ..246/l69A 2,751,582 6/1956 Kuykendall ..340/366R 2,803,807 8/ 1957 Butler ..340/ 8 R 3,064,575 11/1962 Schermuly .1 102/376 FOREIGN PATENTS ()R APPLICATIONS 1,188,967 9/1959 Francem, ..246/169 A Primary ExaminerRobert o. Sheridan Assistant ExaminerGeorge H. Libman Attorney-Kinney, Alexander, Sell, Steldt & Delahunt ABSIRACT A novel device and system are provided for the detection of overheated journals and bearings on a moving vehicle. In one embodiment retroreflective material is propelled to the roadway beneath the vehicle, e.g., a train, to form a target. The target is then exclusively detected by an optical scanner located on a rearward portion of the vehicle.

8 Claims,- 3 Drawing Figures SENSING SYSTEM AND DEVICE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to the detection of overheated journals and bearings on a moving vehicle and, more specifically, to the detection of hot boxes on a train.

2. Description of the Prior Art Overheated journals or bearings on a moving vehicle may result in a serious accident if the problem remains undetected. This problem is most apparent, and most serious, in the operation of trains because an overheated journal or beating may result in a derailment.

Journals which have been packed with rags and oil or grease emit clouds of smoke when the journal becomes overheated. For many years the emission of smoke from a journal box was relied upon as the sole means of detecting overheated journals in railroad operations. However, smoke from an overheated journal may not always be detected. For example, at night the smoke may not be visible to one on the train, and tight fitting journal box lids tend to retain the smoke and other vapors within the journal box very efficiently. Furthermore, newer railroad cars have roller bearings instead of journal boxes and these bearings emit much less smoke and order when they fail than does an overheated journal box.

Thus, some method other than visible detection of smoke has been seriously needed in order to detect an overheated journal or bearing before a derailment results. In accordance with this need, various proposals have been made in attempts to alleviate this problem. For example, light generating sources (i.e., flares) have been proposed which would burn to produce a bright light when a journal is overheated. However, these sources would not be particularly effective during daylight hours, and an intense light could be supplied for only a short time. Moreover, such sources are very expensive.

Another system which has been proposed utilizes infrared bolometer detectors. These systems are ordinarily used for a short section of track, e.g., just before entering a large city. This system is tremendously expensive and it does not continuously monitor the journals because the system is only located at the entrance to large freight yards'or cities.

Thus, there-are many disadvantages with the various systems which have been proposed. For example, some of they systems are very expensive, some do not provide continuous monitoring of the journals, and others are dependent upon ambientlight conditions.

THEPRESENT INVENT ON 2. a marker within said housing which is adapted to be displaced from said housing to the roadway to form a visibly detectable target upon the actuation of said heat sensing means;

In another embodiment there is provided a device which comprises a. at least one heat sensing device adapted to actuate above a predetermined temperature, the heat sensing device being adapted to be located within a journal or bearing; b. a target-producing means comprising 1. a source of electrical current which is connected to said heat sensing device,

2. a housing,

3. propellant means which is adapted to actuate upon receipt of an electric current from said source when said heat sensing device is actuated,

4. a marker within said housing which is adapted to be displaced from said housing to the roadway upon the actuation of said propellant means.

There is also provided a novel system for the detection of overheated journals or bearings which, in one embodiment, comprises the novel device described above and an optical projection and scanning device located on a rearward portion of the vehicle. A heat sensing device is located within at least one journal or bearing on the moving vehicle. When the journal or bearing becomes overheated, the heat sensing device actuates and allows electrical current to actuate the propellant means whereby the marker is displaced from the housing to the roadway to form a target. The optical projection and scanning device on the rearward portion of the vehicle scans the roadway beneath the vehicle and exclusively or selectively detects the target and thereafter produces a warning signal.

The invention will be described in more detail hereinafter with reference to the accompanying drawings wherein like reference characters refer to the same parts throughout the several views and in which:

FIG. 1 is a cross sectional view of one embodiment of a detection device made in accordance with the invention;

FIG. 2 shows railroad car trucks equipped with detection devices of the invention; and

FIG. 3 shows a replacement loading for the detection device.

Referring first to FIG. 1 there is shown generally a device 10 for detecting overheated journals or bearings. The device comprises at least one heat sensing device 12 which is connected by wires 14 to the target-producing means of the device. Heat sensing device 12 preferably is a bimetallic switch. The targetproducing means comprises a source of electrical energy' 16 (which is shown here as 'a small battery), a housing 18, propellant means 24, and marker 26. Housing 18 may have a main portion 22 and a detachable portion or cover 20 so as to provide easy access to the propellant means 24. A mounting bracket 28 may be affixed to the housing 18 so that the device 10 may bev mounted on the vehicle. A plug or stopper 30 may be inserted in the open end of the housing to prevent marker 26 from being prematurely dropped to the roadway.

A blow plug 32 may be'provided on housing portion 22 in such a manner that plug 32 is displaced from the housing when the marker 26 is propelled out the open end of the housing portion 22. The portion 33 of thehousing which lies behind plug 32 may be painted with a very conspicuous color, e.g., bright red or orange. Thus, the brightly colored portion 33 of the housing is easily noticed after the propellant means has displaced marker 26 and plug 32 from the housing.

Although the source of electrical energy 16 is shown as a small D C battery (1.5 volts), the electrical current may also be provided by an external source, e.g., from an electrical system on the moving vehicle itself. When a battery is used as the electrical current source, it is preferred to mount the battery within the housing (as shown in the drawing) so that it will not be affected by dirt, moisture, grease, etc.

Propellant means 24 is preferably an explosive charge which is adapted to detonate upon the receipt of an electrical current. For example, the propellant means may comprise a commercial explosive charge such as Ignition Cartridge Model 1375 (sold by Holex, Inc.). The propellant means may also comprise a source of compressed air or gas or it may even be a mechanical spring. The function of the propellant means is merely to displace the marker from the housing when the heat sensing device is actuated.

Marker 26 forms a visibly detectable target when it is dropped or propelled to the roadway. Thus, marker 26 may comprise paint or any other visibly detectable substance. Preferably marker 26 comprises light-reflecting means such as fluorescent materials or retroreflective materials. For example, a fluorescent marker or target be detected by a scanner which is sensitive to ultraviolet light. When the detection device contains means to propel] the marker onto the roadway, it is possible to package the marker in a plastic bag which will burst upon hitting the roadway. When the marker is to be simply dropped to the roadway, the packaging, if any, should be capable of bursting immediately to allow the marker to form a visibly detectable target.

If'desired, one may use various ordoriferous materials in conjunction with visibly detectable materials for the marker. In such a case two scanners would be used in conjunction with each other to detect the target made by the marker. Thus, the possibility of producing a false alarm signal would be greatly reduced by requiring both types of scanners to detect the target.

The most preferred markers or targets are the retroreflective materials. These include reflective elements such as transparent glass microspheroids with a thin metallic reflector coating, e.g., aluminum, over approximately half of their area, as described in U.S. Pat. No. 2,963,378. Reflective granules described in U.S. Pat. No. 3,043,196 are also very useful.

Another retroreflective material which is very useful is a paste composition comprising retroreflective elements dispersed and suspended in a vehicle, the vehicle comprising a volatile solvent and a gellating agent which causes the vehicle to gel. The retroreflective elements are preferably transparent glass beads that have been hemispherically coated with a light-reflective material, e.g., aluminum. Uncoated glass beads are also useful if a reflective pigment such as metal flake or powder is included in the vehicle. Another composition which is very useful comprises retroreflective elements in an adhesive binder, the retroreflective elements having been hemispherically coated with a light-reflective material such as aluminum.

The retroreflective target produced by marker 26 may be made self-destructable by including with the marker. in a separate package, a strong base which would decompose the thin metallic coating on the glass beads after a short period of time. For example, strong bases such as sodium hydroxide may be useful for this purpose.

Referring next to FIG. 2 there are shown two railroad trucks 40 with which have been equipped with detection devices 10. Wires 14 connect the target-producing means with the heat sensing devices 12, which are mounted within journals or bearings 42. In this fashion, only one target-producing means is required to service one truck, with a heat sensing device'12 being located in each of the four journal or bearings on the truck. When a journal becomes overheated, the heat sensing device actuates and allows an electrical current to actuate the target-producing means, causing a marker to be displaced from the target-producing means to the roadway beneath the train or vehicle to form a target 44. A scanner located on a rearward portion of the train or vehicle will then detect the target which is laying on the roadway beneath and thereafter produce a warning signal.

Various scanning devices may be used in the detection system. For example, when the target is a retroreflective material, an optical projection and scanning device may be used to detect the target. For example, such photoscanning devices are commercially available from Machinery Electrification, Inc. as Model 5330, from Photoswitch as Model 42RE1, from General Electric as Model SC50lA6 or from Loepfe. These photoscanners include a light source which sends out one or more beams of light and a photoelectric cell adjacent each beam of light that develops an electric signal whose magnitude depends on the amount of light that strikes the cell. A very useful photoscanner which projects a curtain of light rather than a beam is available from Erwin Sick Co. in their LV series. The photoscanner is adapted to produce a warning signal, e.g., a buzzer or flashing light, to alarm someone in the caboose or passenger car of the train. The photoscanner may even be connected with an electromechanical device to trigger the braking system of the vehicle or train.

In order to prevent the target from giving a false alarm to a following train, the photoscanner may be adapted to trigger a target-covering means, e.g., a loading of dark paint which is propelled to the roadway to cover the light-reflecting target.

In FIG. 3 there is shown a unitary replacement loading 46 for the detection device 10. The loading 46 comprises a propellant means 48 and a marker 50. Such a replacement loading is designed for very fast and efficient recharging of the detection device. For example, the replacement loading may be simply inserted into the top portion of the housing with the marker 50 aiming or pointing toward the bottom portion of the housing. Lip 52 on the top of the replacement loading prevents the explosive charge from falling down into the main portion of the housing.

Another embodiment of the replacement loading comprises a propellant means and a marker contained within a barrel] housing similar to that of housing por- -tion 22 shown in FIG. 1. In this embodiment the housing is adapted to be detachably mounted or connected to a second housing (similar to housing portion 20 in FIG. 1) which is fixedly mounted on the vehicle. The second housing contains the source of electrical current and the lead wires to the heat sensing device. Thus, the detection device may be simply recharged or reloaded by detaching the barrell housing and replacing it with a barrell housing which contains a marker of lightreflecting material and a live explosive charge.

What is claimed is: 1'. A system for detecting overheated journals or bearings on a moving vehicle comprising a. heat sensing means which is adapted to actuate when a journal or bearing reaches a predetermined temperature, b. target-producing means comprising 1. a housing, and 2. a marker within said housing which is adapted to be displaced from said housing to the roadway to form a visibly detectable target upon the actuation of said heatsensing means, and c. an optical scanning device located on a rearward portion of said vehicle which is adapted to scan the roadway beneath said vehicle and which is further adapted to exclusively detect said target and thereafter produce a warming signal. 2. A system for detecting overheated journals or bearings on a moving vehicle comprising a. at least one heat sensing device adapted to actuate,

when a journal or bearing on said vehicle reaches a predetermined temperature;

b. a target-producing means comprising 1. a source of electrical current which is connected to said heat sensing device, 2. a housing,

3. propellant means which is adapted to actuate 7 upon receipt of an electrical current from said source when said heat sensing device is actuated,

4. a marker within said housing which is adapted to be displaced from said housing to the roadway to form a visibly detectable target upon the actuation of said propellant means, and

c. an optical scanning device located on a rearward portion of said vehicle which is adapted to scan the roadway beneath said vehicle and which is further adapted to exclusively detect said target and thereafter produce a warning signal.

3. The system of claim 2, wherein said source of electrical energy is a battery.

4. The system of claim 2, wherein said propellant means comprises an explosive charge which is adapted to detonate upon receipt of said electrical current.

5. The system of claim 2, wherein said marker com- 

1. A system for detecting overheated journals or bearings on a moving vehicle comprising a. heat sensing means which is adapted to actuate when a journal or bearing reaches a predetermined temperature, b. target-producing means comprising
 1. a housing, and
 2. a marker within said housing which is adapted to be displaced from said housing to the roadway to form a visibly detectable target upon the actuation of said heat sensing means, and c. an optical scanning device located on a rearward portion of said vehicle which is adapted to scan the roadway beneath said vehicle and which is further adapted to exclusively detect said target and thereafter produce a warming signal.
 2. a marker within said housing which is adapted to be displaced from said housing to the roadway to form a visibly detectable target upon the actuation of said heat sensing means, and c. an optical scanning device located on a rearward portion of said vehicle which is adapted to scan the roadway beneath said vehicle and which is further adapted to exclusively detect said target and thereafter produce a warming signal.
 2. A system for detecting overheated journals or bearings on a moving vehicle comprising a. at least one heat sensing device adapted to actuate when a journal or bearing on said vehicle reaches a predetermined temperature; b. a target-producing means comprising
 2. a housing,
 3. propellant means which is adapted to actuate upon receipt of an electrical current from said source when said hEat sensing device is actuated,
 3. The system of claim 2, wherein said source of electrical energy is a battery.
 4. The system of claim 2, wherein said propellant means comprises an explosive charge which is adapted to detonate upon receipt of said electrical current.
 4. a marker within said housing which is adapted to be displaced from said housing to the roadway to form a visibly detectable target upon the actuation of said propellant means, and c. an optical scanning device located on a rearward portion of said vehicle which is adapted to scan the roadway beneath said vehicle and which is further adapted to exclusively detect said target and thereafter produce a warning signal.
 5. The system of claim 2, wherein said marker comprises light-reflecting means.
 6. The system of claim 5, wherein said marker comprises fluorescent material.
 7. The system of claim 5, wherein said marker comprises retroreflective material.
 8. The system of claim 5, wherein said battery is located within said housing and is electrically connected in series between said heat sensing device and said explosive charge. 